Protective helmet liner



FIG. 1 is a front elevational view of a protective helmet linerembodying the new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a botton plan view thereof; and,

FIG. 5 is a right side elevational view thereof, the left side being amirror image of the right side.

The broken line showing of helmet is included for the purpose ofillustrating environment and forms no part of the claimed design.

We claim the ornamental design of a protective helmet liner, as shownand described.